Region-of-interest video compression is often used when compressing a video stream comprising one or more regions-of-interest. The term “region-of-interest” is intended to include, but is not limited to, one or more areas within a video frame or plurality of video frames (i.e., a video stream) that contain information of interest to a viewer. For example, within a surveillance setting wherein a surveillance camera for a convenience store generates a video stream, the region-of-interest may be the portion of the video stream capturing the activity within the doorframe of the convenience store. If the video stream from the surveillance camera was to be used to identify a robber entering the convenience store, the portion of the video stream capturing the activity within the doorframe may be the most important information within the video stream. As such, the area within the doorframe would be referred to as the region-of-interest. At the same time, the information within the video stream representing the floor or ceiling may not be of particular importance and would not be defined as a region-of-interest. The region-of-interest may be a fixed location for all video frames included in a video stream, however, the location of a region-of-interest may move between video frames within a video stream. For example, if a region-of-interest corresponds to a moving body within a video stream, the location of the region-of-interest may shift from video frame to video frame in order to track the body's motion. In addition, the size of a region-of-interest may change between video frames.
Given that the region-of-interest is of greater importance than the non-region-of-interest, region-of-interest video compression functions to create a higher quality video image within the region-of-interest in comparison to the non-region-of-interest. As a result, region-of-interest compression applies a greater amount of video compression to the non-region-of-interest portion of a video stream in comparison to the region-of-interest-portion. This methodology minimizes the degradation of video quality within the region-of-interest while allowing for a greater amount of compression to be applied to the non-region-of-interest portion of the video. Therefore, the video quality within the region-of-interest may be maintained at a higher level, in comparison to the video quality outside of the region-of-interest.
According to conventional region-of-interest compression methods, applying different levels of video compression to a region-of-interest versus a non-region-of-interest requires the use of a region-of-interest parameter set. The region-of-interest parameter set dictates the level of compression to be applied to each region within a video frame. According to conventional region-of-interest compression methods, a parameter set generation module receives a video stream and creates a region-of-interest parameter set based on the video frames within the video stream. The region-of-interest parameter set includes detailed instructions dictating the way in which a given encoder is to compress each region within a corresponding video frame, herein referred to as the “compression instructions”. In order for the encoder to effectively compress a given video frame, the parameter set generation module must create a region-of-interest parameter set in a language and/or format understood by the specific encoder that will be performing the video compression. As a result, the parameter set generation module must be configured to produce a region-of-interest parameter set that may be understood and effectively used by the encoder to compress the corresponding video frame.
According to conventional region-of-interest compression methods, if a new or alternative encoder is to be utilized, the configuration of the parameter set generation module must be altered to ensure that the parameter set generation module creates a region-of-interest parameter set understandable by the encoder. As a result, new or alternative encoders may not be introduced into a conventional region-of-interest compression method without modifying the parameter set generation module. Therefore, in instances where cheaper, more effective, or more efficient encoders are available, conventional region-of-interest compression methodologies do not allow for these encoders to be seamlessly integrated into the conventional compression methodologies.
As a result, there is a need in the art for a method, system or computer-readable medium for performing region-of-interest video compression, wherein a variety of encoders may be seamlessly coupled to or integrated into the method, system or computer-readable medium.